Introduction¶
In this project we’ll be analyzing a data set containing information about 10,000 movies collected from The Movie Database (TMDb). We will try to answer the following questions:
Which genres are most popular from year to year?¶
What properties are associated with highly profitable movies?¶
%matplotlib inline
%config InlineBackend.figure_format = 'retina'
import numpy as np
import pandas as pd
import matplotlib.pyplot as plt
import matplotlib.ticker as ticker
import matplotlib.animation as animation
import seaborn as sns
from IPython.display import HTML
Loading Data¶
Let's load data from a CSV file and print out a few lines.
df = pd.read_csv('tmdb-movies.csv')
df.head(2)
df.shape
We'll be analyzing a dataframe with 21 columns and 10866 entries. We notice that the columns “cast”, “genres” and “production_companies” contain multiple values separated by the '|' character.
df.info()
There are several columns with missing values. For example, "homepage" has only 2936 values, and "tagline" has 8042 values. Luckily, all these columns do not make any sense for further analyzing and can be dropped. So the first thing we're going to do is drop all unnecessary columns.
Cleaning Data¶
Drop Unneccessary Columns¶
df.drop(['id', 'imdb_id', 'homepage', 'tagline', 'keywords', 'overview'],
axis=1,
inplace=True)
df.shape
Now we have only 15 columns left.
Change Data Type of "release_date"¶
We notice that "release_date" Dtype is the object. It means the date is in string format. It's better to convert it to the special datetime format.
df.release_date = pd.to_datetime(df['release_date'])
df.info()
Generate Descriptive Statistics¶
df.describe()
The columns "budget", "budget_adj", "revenue", "revenue_adj", and "runtime" have zero values. Obviously, these values can't be zero, and I think they should be replaced with "NaN" so they’ll not influence the statistics.
Replace Zero Values with "NaN"¶
df['budget']=df['budget'].replace(0, np.nan)
df['budget_adj']=df['budget_adj'].replace(0, np.nan)
df['revenue']=df['revenue'].replace(0, np.nan)
df['revenue_adj']=df['revenue_adj'].replace(0, np.nan)
df['runtime']=df['runtime'].replace(0, np.nan)
df.describe()
Show Distibution of Data¶
df.hist(figsize=(10,8));
We notice that the histograms labeled “budget”, “revenue”, "popularity", "vote_count" are extremely right-skewed. The max values of these columns stand out from all of the other numbers. For example, the mean value of "popularity" is around 0.64, the standard deviation is around 1.0, and 75% of the values are lower than 1.0, but the max value is almost 33!
The histogram of "release_year" is left-skewed, which means the number of movie releases increases every year.
The histogram of "vote_average" is almost normally distributed as it should be.
Final Data¶
df.info()
There are still several columns with null values. But it makes no sense to drop these entries. A better tactic would be to use as much data as possible for every question.
Exploratory Data Analysis¶
Now that we've trimmed and cleaned our data, we're ready to move on to exploration. We will compute the statistics and create visualizations with the goal of addressing the research questions that we posed in the Introduction section.
Research Question 1: Which genres are most popular from year to year?¶
To answer this question we'll create an animated horizontal bar chart.
References¶
Animated bar chart, https://towardsdatascience.com/bar-chart-race-in-python-with-matplotlib-8e687a5c8a41
Splitting values, https://medium.com/@lsriniv/splitting-columns-of-series-dataframe-into-rows-step-by-step-explanation-9fce88ed1144
Previously we mentioned that “genres” column contains multiple values separated by the '|' character. So we have to split them in order to create a list of all genres.
genres = df.genres.str.split('|', expand=True).stack().value_counts().index
print("Number of genres is {}".format(genres.size))
We have 20 genres overall. Let's create a color map for them, so that every genre will have a unique color. Choosing colors is a very complicated task, so we’ll use the built-in matplotlib “tab20” colormap that has exactly 20 colors with a good-looking palette.
colors_map = {}
cm = plt.cm.get_cmap('tab20')
#we have 20 colors in [0-1] range
#so start from 0.025 and add 0.05 every cycle
#this way we get different colors for
#every genres
off = 0.025
for genre in genres:
colors_map[genre] = cm(off)
off += 0.05
Let's create a function that returns a sorted dataframe with dependency of values from a multiple value column and a single value column. This will help us to analyse all multiple values columns.
def get_mdepend(df, multival_col, qual_col):
#split column by '|' character and stack
split_stack = df[multival_col].str.split('|', expand=True).stack()
#convert series to frame
split_frame = split_stack.to_frame(name=multival_col)
#drop unneeded index
split_frame.index = split_frame.index.droplevel(1)
#add qual_col, group and find average
dep = split_frame.join(df[qual_col]).groupby(multival_col).mean()
#return sorted dependency
return dep.sort_values(qual_col)
Next we'll create a function that plots our horizontal bar chart with the popularity of movies for all genres up to the desired year.
def draw_barchart_frame(current_year):
#get data only up to current_year
dep = get_mdepend(df.query('release_year <= {}'.format(current_year)),
'genres', 'popularity')
#clear before draw
ax.clear()
#plot horizontal barchart using our colormap
ax.barh(dep.index,
dep['popularity'].tolist(),
color=[colors_map[x] for x in dep.index])
#plot genres and values
dx = dep.max() / 200
for i, (value,
name) in enumerate(zip(dep['popularity'].tolist(), dep.index)):
#genre name
ax.text(value - dx,
i,
name,
size=14,
weight=600,
ha='right',
va='center')
#genre value
ax.text(value + dx,
i,
f'{value:,.2f}',
size=14,
ha='left',
va='center')
#big current year
ax.text(1,
0.2,
current_year,
transform=ax.transAxes,
color='#777777',
size=46,
ha='right',
weight=800)
#plot caption of ticks
ax.text(0,
1.065,
'Popularity',
transform=ax.transAxes,
size=14,
color='#777777')
ax.xaxis.set_major_formatter(ticker.StrMethodFormatter('{x:,.1f}'))
ax.xaxis.set_ticks_position('top')
ax.tick_params(axis='x', colors='#777777', labelsize=12)
ax.set_yticks([])
ax.margins(0, 0.01)
ax.grid(which='major', axis='x', linestyle='-')
ax.set_axisbelow(True)
#chart caption
ax.text(0,
1.16,
'Popularity of movie genres from 1960 to 2015',
transform=ax.transAxes,
size=24,
weight=600,
ha='left',
va='top')
Finally we'll create an animation.
#create figure
fig, ax = plt.subplots(figsize=(10, 7))
#remove borders
plt.box(False)
#immediately close it to not provide additional figure
#after animation block
plt.close()
animator = animation.FuncAnimation(fig,
draw_barchart_frame,
frames=range(1960, 2016),
interval=666)
#add space before animation
print('')
HTML(animator.to_jshtml())
Research Question 2: What properties are associated with highly profitable movies?¶
Preparing Data¶
We have to get data only with the budget and revenue values available. Also I think it's better to use adjusted values so that money inflation doesn't interfere with our calculations.
dfp = df[df.budget_adj.notnull() & df.revenue_adj.notnull()].copy()
dfp['profit'] = dfp.revenue_adj - dfp.budget_adj
Correlation¶
Let's try to find if there is any correlation with profit.
sns.pairplot(data=dfp,
x_vars=['popularity', 'budget', 'runtime'],
y_vars=['profit'],
kind='reg');
sns.pairplot(data=dfp,
x_vars=['vote_count', 'vote_average', 'release_year'],
y_vars=['profit'],
kind='reg');
"popularity" and "vote_count" have a positive correlation with profit. Obviously, the more people who watch the movie, the more revenue it gets.
"budget" has a small positive correlation with profit. So we can conclude that higher investments in movies cause higher revenues.
Surprisingly, "vote_average" has a weak positive correlation with profit.
Setup Default Plot¶
Let's configure the default parameters for our plots, such as figure size and font sizes.
params = {
'legend.fontsize': 'x-large',
'figure.figsize': (10, 8),
'axes.labelsize': 'x-large',
'axes.titlesize': 'xx-large',
'xtick.labelsize': 'x-large',
'ytick.labelsize': 'x-large'
}
plt.rcParams.update(params)
Next we will implement a function to plot a profit chart.
def profit_chart(df, title):
#create figure
ax = df.plot(kind='barh')
#remove legend from plot
ax.get_legend().remove()
#set custom axis formatter for millions
ax.xaxis.set_major_formatter(
ticker.FuncFormatter(lambda x, p: format(int(x / 1e6), ',')))
#set titles and labels
plt.title(title)
plt.xlabel('Average Profit ($ million)')
plt.ylabel(None)
Genre¶
Let's find out how profit depends on genre.
profit_chart(get_mdepend(dfp, 'genres', 'profit'), 'Movie Profits By Genre')
Production Company¶
There are a lot of production companies. Let's find out what are the most profitable production companies.
profit_chart(
#last 10 values
get_mdepend(dfp, 'production_companies', 'profit').tail(10),
'Top 10 Profitable Production Companies')
Cast¶
Let's find out what are the most profitable actors.
profit_chart(
get_mdepend(dfp, 'cast', 'profit').tail(10), 'Top 10 Profitable Actors')
Release Year¶
Let's look at how profit depends on release year.
year_profit_mean = dfp.groupby('release_year')['profit'].mean()
#rolling average over 10-years
year_profit_rol = year_profit_mean.rolling(window=10).mean()
ax = year_profit_rol.plot(figsize=(12, 8))
#set custom axis formatter
ax.yaxis.set_major_formatter(
ticker.FuncFormatter(lambda y, p: format(int(y / 1e6), ',')))
#set titles and labels
plt.title('Movie Profits By Year')
plt.ylabel('Average Profit ($ million)')
plt.xlabel("Release Year");
We can see how huge the difference is between profits in 1980s and nowadays. It is probably connected to the fact that the number of movies every year increased accordingly. Let's quickly look at a graph to determine if this is true.
#we know that popularity column has no nulls
#so use it for counting the number of movies
ax = df.groupby('release_year')['popularity'].count().plot(figsize=(12, 8))
#set titles and labels
plt.title('Number Of Movies Per Year')
plt.ylabel('Number Of Movies')
plt.xlabel("Release Year");
We notice that the number of movies moves in the opposite direction of movie profits year-by-year.
Conclusions¶
Finally, we can summarize our findings and answer questions from the Introduction section.
By looking at animated bar charts of genres' popularity, we can watch how movie trends changed over the years.
- "Animation" and "Adventure" are the most popular genres and they competed with each other for the whole period of time.
- The least popular genres were "Documentary" and "Foreign".
- "TV Movie" was popular before 1970 but then rapidly became extremely unpopular.
- "Science Fiction" was extremely unpopular before 1970 but then rapidly became one of the most popular genres.
- "Fantasy" gradually increased in popularity and became very popular recently.
Properties of high profit movies:
- High budget.
- High popularity.
- Genre is one of these: "Animation", "Adventure", "Family", "Fantasy" and "Science Fiction".
- Production companies are one of these: "Hoya Productions", "Truenorth Productions", "Alfran Productions".
- The cast of the movie includes these actors: "Jason Miller", "Robert MacNaughton", "Daisy Ridley".
- Release year is prior to the 1980s.
Limitations: There is a lot of missing data in the dataset.